This invention relates to chilling or cooling workpieces that are fed to an assembly line station, e.g., to shrink the workpieces so that they can be fit or pressed into a larger assembly.
It is useful to chill workpieces that are fed to an assembly line, particularly metal parts that must be shrunk so that they can be fit or pressed into a larger assembly. For example, valve seats, valve guides, or cylinder liners can be chilled so that they can be fit or pressed into the cylinder head or block of an internal combustion engine.
Various means of cooling or chilling workpieces have been proposed. For example, Ross U.S. Pat. No. 2,218,722 discloses workpiece-chilling device for use on an assembly line. The device has a chilling tray 107 (FIG. 11) which contains in compartment 108 (FIG. 12) a chilling agent, as for example, temperature controlling liquid air, and which contains in compartment 109 a light fuel oil.
Colestock U.S. Pat. No. 3,621,550 discloses a refrigeration chamber to chill valve seats 10 that are stored in a vertical magazine 12. The valve seats are chilled to below 0.degree. C. by some unspecified mechanism in a refrigerator chamber. The chilled valve seats are transferred from the bottom of the magazine (by a pneumatic cylinder) to an assembly station.
Other prior art concerns apparatus for chilling individual parts, not necessarily in connection with an assembly line.
Emerich U.S. Pat. No. 1,980,156 discloses means for making an expansion fit using CO.sub.2 to shrink bushings 17. A cylindrical head 18 receives CO.sub.2 through flexible pipe 34.
Allen et al. U.S. Pat. No. 1,955,728 discloses a method and tool for inserting bushing 15 in, or removing it from, outer member 16, by spraying the bushing with CO.sub.2 and a low-freezing point liquid. The tool is inserted into the bushing before spraying.